Monday, January 13, 2014

Home Birth Safety

Edit 01/31/2013: I need to add the latest study offering up insight on home birth safety here in the USA. Click here to read it. It, yet again, shows increase risk for babies born at home.I originally wrote this as a post in a forum online
but I decided I wanted to share it here as well. This post addresses the peer
reviewed studies regarding safety of home birth in our country.

It is important to know that studies done in other countries to "prove" the safety of
home birth do not apply to home birth
midwifery in the United States. Countries like the Netherlands, the UK,
Canada, etc have home birth midwifery
integrated into their health care systems. Their midwives have different
education and training... more similar to a CNM or CM here in the USA. CPMs and
LMs are a different story though, but they are the ones who attend majority of
home births in the USA. CPMs and LMs do not have hospital privileges. They
are not comparable to midwives in other first world countries in terms of
education and training, as most CPMs and LMs go through a direct-entry process
that has no education requirements (until September 2012 it did not even
require a high school diploma). There are other differences as well that I have
discussed in other blog posts (here and here).

For various other reasons, home birth in the United
States cannot be compared to home birth midwifery in other first world
countries. It's comparing apples to oranges.

Is home birth safe here in the USA? What we have for information to answer that question are 4 peer reviewed studies
plus the CDC Wonder Database, all of
which show an increase risk for babies born at home. Here are the 4
studies:

This study is the most well-known study in the home
birth community and the only study
that supposedly shows the proof that "home birth is just as safe as
hospital birth." But this study has two fatal flaws and it actually shows
the opposite, that home birth increases
the risk for babies.

First, the authors compared intervention rates
between home and hospital for the same year, 2000. But when they compared
mortality rates between home and hospital, they used the year 2000 for the home
birth rates BUT for hospital rates, they used several papers dating back to
1969. Why didn't they compare hospital rates for the same year? Because if they
would have, you find the rate to be double
to triple the risk. The authors claimed that they did not have the hospital
data available for the year 2000 when they published their study, which is why
they used the dated papers. You can read a critique here which shows the
numbers:

It is also important to note that crucial data is missing from this
study. In Autumn of 1999, NARM contacted all registered CPMs regarding
this study. Not everyone could be contacted, not everyone planned to
re-certify, not everyone agreed to participate. So they were left with 409 midwives.
All 409 midwives AGREED to take part in this study. Yet, 18 midwives ended up
not having their births used in the study - those 18 midwives were not able to
re-certify because participation was mandatory in order to do so.... however, this
does NOT mean those midwives are not still practicing. Where is the data on
those 18 midwives and their births? Why did they AGREE initially to take part?
What if they each had an infant or mother die under their care and that's why
they did not complete the process? This essentially means midwives who had bad
outcomes could bow out after the fact and those outcomes would then not be
included in the study.

These are two serious flaws. This is a study I once
was totally behind.... this is what I had my husband (and others) read when we
were planning for our home birth, this was my "proof" of home birth
safety. I was completely unaware of these flaws at that time. I even wrote a
response on the article in the British Medical Journal regarding the missing data on those 18 midwives but I have
yet to hear a response.

This study shows a triple neonatal mortality rate
for babies born at home vs in a hospital but it isn't a high quality study because there are births included in the home birth group that did not have a midwife
present (in other words, births that were intended to be hospital births that were accidental home births).

These two studies both show the risk to babies
is significantly higher for death, seizures or serious neurological
dysfunction for babies born at home and freestanding birth center. Home birth
and birth centers were compared to hospital births with OBs (which would
include high risk pregnant women) and hospital births with CNMs.
Hospital
births with CNMs had the lowest rates (meaning, best outcomes -- which would
make sense b/c it would be low risk women). Followed by hospital birth with a doctor. A fairly significant higher risk is midwife-attended birth center birth. The highest risk - by an incredibly significant amount - was home birth with a midwife.

Some home birth advocates are trying to say these
studies are not valid because they use unplanned home births - this is NOT true. They used data ONLY from home and birth
center births where a midwife was present. If it was not midwife-attended
or if it was unknown whether or not there was an attendant, the data was not
used.

One of the limitations in the studies is actually
home birth transfers to hospitals that resulted in death... those would be
counted in the hospital group. This would obviously make the neonatal mortality
rate even higher for home births if those deaths were counted in the home birth
group.

This response from MANA could not provide a better example of
why I have ZERO respect for that organization. It is full of lies
and utter nonsense.

First, they try to dismiss the findings by saying
birth certificates "are not very accurate when it comes to rare outcomes
like very low Apgar scores, seizures, or deaths (Northam & Knapp, 2006)."

In the comments, someone wrote that the study they
reference actually states the opposite, it states that APGAR scores are
actually quite accurate on birth certificates. So I read the study. And it
indeed does say that APGARs are reliable on birth certificates. Each time APGAR scores are mentioned in the study, it mentions that APGAR scores are one of the more reliable pieces of information on birth certificates. To quote the very study they reference exactly it says “Birthweight, Apgar score, and delivery
method agreed 91.9% to 100%. The high-percent agreement supports the
reliability of those variables.” So not only did they offer up completely
false information, but then when someone pointed it out to them, they did
nothing to edit or change it.

Next, they say that it is a fatal flaw to use birth
certificate info because birth certificates don't adequately capture intended place
of birth. But intended place of birth doesn't matter for this study - actual place of birth is what is most important. And the place of birth is adequately captured. The data used in these studies was only midwife attended births at home or at freestanding birth centers. As I said above, if it was unknown whether or not an attendant was present or
if there was no attendant at all, the data was not used. So again, their
second “flaw” with the article is yet again, not actually a flaw.

Then they say this "In recent
well-designed studies that captured planned place of birth and used better sources
of data, there were no differences in 5-minute Apgar scores between home and
hospital settings (Hutton et al, 2009; Janssen et al, 2009; van der Kooy et al,
2011)." How incredibly shocking!! Yet again, MANA is trying to prove a
point about safety by using studies based in other countries -- the first two
studies are out of Canada and the third is out of the Netherlands. How on earth
does this apply to the findings of these studies? IT DOESN’T. It literally takes nothing
away from the findings of these studies.

Finally they offer this "They analyzed the rare
occurrence of 5-minute Apgar scores of zero, which may be indicative of a
number of possible events which may or may not have been related to the time,
location or care provider at the birth. The authors note that stillbirths may
have occurred in the third trimester, may have been due to lethal congenital
anomalies, and other possibilities that are captured in a 5-minute Apgar score
of zero." However, if you read the study, they address this. And although it is considered a limitation that
antepartum deaths may be included, it likely wouldn't change the findings because intended home or birth center antepartum deaths would be transferred to the hospital for delivery. What midwife
would keep a woman at home to deliver the baby if she couldn't hear a heartbeat
at the beginning of labor?? The chances of any third trimester stillbirths
being included in the home birth group are slim to none.

That covers their critique of the studies. They were
grasping and officially grabbed onto nothing.

The fact is, these two studies are very high
quality. No, not perfect. But the findings should certainly not be dismissed.
They should be addressed. And they certainly should be considered for those looking into home birth.

****

So that’s that.

While home birth can
be safe, the truly safe scenarios are
the exception, not the rule. All evidence points toward an increase risk at
home. I have no doubt it is largely due to the lack of training and education
of the birth attendants.

I have more to say… including my thoughts on what
situations I would call “safe” for home birth and thoughts on the CPM/LM credential…
but I will end this particular post here. Stay tuned…

01/14/2013 Update:I added a blog post addressing guidelines for having a safe home birth. Click here to read it.

Northam and Knapp do say on p. 9 that "Studies involving rare events, such as some congenital anomalies, are less accurately reported when only 1 year of data were used in analysis." And on p. 10, "The use of mul-tiple years in evaluating trends of infrequently occurring problems reduces error. When only short time frames are used, infrequent occurrences are greatly impacted by small number changes. The appendices of NCHS publications include recommendations to researchers for managing data error particularly when small numbers are involved." It's a difficult paper for a lay person to read (and you have to pay $6.45 to rent it from ReadCube), but as far as I can tell, they didn't make any explicit connection between the difficulty in measuring rare events with the reliability of data on low Apgar scores. So the paper shouldn't confidently be used to discredit data on low Apgar scores. In addition to this study, Grunebaum et al. cite other studies that demonstrate the reliability of Apgar score data on birth certificates.

I also wonder if some rare events are inherently more likely to be recorded incorrectly on birth certificates than others. Are Apgar scores as susceptible to this bias as congenital abnormalities?